In the field of art, especially of painting, artists frequently work on large-sized grounds. These are conventionally in the form of canvas which is tension-mounted on stretchers. Occasionally, other ground materials such as wood or cardboard blocks and the like are also used.
These painting grounds have to be held by specific devices as they are being worked. Conventionally, the painting grounds are therefore fixed on an easel whilst the artist is working. Easels of this kind are known, in which the painting grounds are fixed tightly. The connection is generally effected by the canvas, which is drawn onto a stretcher, being clamped in place. Whenever, therefore, a canvas frame (stretcher) is fastened to the easel, a static, immovable connection exists between the canvas frame (stretcher) and the easel.
The object of the present invention is to provide further easels which enable the artists to work better.
Professional painters normally work in a certain style. An essential component part of this style is also the manner in which the brush or the painting tool is guided. Most artists have a particular direction and a particular uniqueness in terms of their stroking. This particular style, which is dependent upon the line composition, is conventionally practiced by the artists in a specific posture which can vary from artist to artist. The easel described below according to the invention enables the artist to work in an optimal manner, since that place on the canvas which is to be worked can be adapted to the posture of the artist which is optimal for working.
An essential component part of the easel according to the invention is the support element. This support element can be fitted approximately at a right-angle to a preferably mobile stand. A static fastening of the support element in certain rooms, such as, for example, in studios, would also be conceivable. The stand bearing the support element can be provided with rollers to enable the easel to be displaced without difficulty. The wheels or rollers of the stand can preferably be at least partially secured.
In a preferred embodiment, the support element is formed by a column. This column can be formed, for example, by two sectional rails disposed parallel to each other. Recesses on the edges of the sectional rails can serve as rails for the holding element, which can be moved in these rails by means of rollers or wheels. An essential feature is that the one, central column is designed such that the interior is hollow and at least one, or better still, two sides remain free, so that the holding element fitted on the support element is also able to extend into the interior of the support column. One embodiment of the easel, according to the invention, having a central column, is represented by way of example in FIG. 1.
In another embodiment, the support element exhibits two support columns which are disposed parallel to each other and to which the holding element is fitted. An embodiment of this type is represented, for example, in FIG. 2.
In a further embodiment, the easel according to the invention exhibits three support columns. An embodiment of this type is represented diagrammatically in plan view in FIG. 3.
For certain embodiments, especially where particularly large or heavy objects are to be held by the easel, the support element can also exhibit four or more columns.
Movably fitted to the support element is a holding element which, together with a fastening device, forms the connection to the object to be held. What is preferably meant by a movably fitted holding element is that the holding element can be moved over a large part of the support element. Depending upon the constructional design of the easel according to the invention, various forms of the holding element are usable. In the embodiment shown in FIG. 1, the holding element constitutes a box which encloses the support column and projects into the interspace between the two sectional rails. FIG. 4 shows diagrammatically the arrangement of the holding element in relation to the support element formed by the sectional rail. In this embodiment, the box-shaped holding element exhibits eight wheels or rollers, which are disposed such that they fit into the recesses in the sectional rails and produce a precise-fitting, movable connection. That part of the box-shaped holding element which projects into the interspace between the two sectional rails supports in a preferred manner the drive means, preferably an electric motor, for the vertical movement, as well as the drive means, preferably an electric motor, for the rotational movement which can be exerted upon the fastening device.
In another preferred embodiment of the present invention, the holding element constitutes a plate which exhibits recesses for the support elements. An embodiment of this type is represented, for example, in FIG. 3. The plate with recesses can move in the vertical direction on the supports. To improve stability, sleeves can be fitted to the recesses of the holding element parallel to the support columns, which sleeves enable the plate to be stabilized against tilts. Here too, there are provided on the holding plate both devices for the movement in the vertical direction and means for the rotational movement of the fastening device.
On the easel various objects can be fastened which are worked by artists. Conventionally, a painting ground is fastened on the easel. The ground in question can take the form of cardboard or wooden blocks, though conventionally, as painting ground, canvas is used, which is normally tension-mounted on stretchers. These stretchers comprise a rectangular lath framework to which the outer margins of the canvas to be worked are fastened. The canvas frames (stretchers) also often exhibit a cross-like reinforcement structure, in which the midpoints of the opposing frame parts are respectively joined together.
In a preferred embodiment of the present invention, the fastening device is rotatable, the axis of the fastening device being disposed at an angle of 45xc2x0-90xc2x0, preferably around 90xc2x0, to the axis of the support element. The respective angle can be adjustable by virtue of suitable constructional embodiments. The connection between the support column and the frame (stretcher) is created by means of the holding element and the fastening device.
In a preferred embodiment of the present invention, the holding element and the fastening device for the canvas frame (stretcher) are designed to be separable from each other.
The fastening device is fastened to the canvas frame (stretcher). Preferably, the fastening is here effected in such a way that the fastening device is connected to the canvas frame (stretcher) by means of clamping members and/or screw connections.
In an especially preferred embodiment of the present invention, the fastening device is fastened to the cross in the canvas frame (stretcher).
In a preferred embodiment, the holding element exhibits a receiving member, which is disposed rotatably about an axis at an angle of around 90xc2x0 to the axis of the support element. The receiving member in question can be a bushing, which is designed such that rotation by an electric motor and, where appropriate, a gear system is made possible.
Into this receiving member there can be introduced the insertion member located on the fastening device. In one embodiment, the insertion member in question is a spigot which fits precisely into the bushing.
The connection between the holding element and the fastening device is preferably designed such that twisting of the insertion member in relation to the receiving member is impossible. This can be achieved, for example, by the receiving member exhibiting recesses and by the insertion member exhibiting elevations which fit precisely into the recesses in the receiving member. The connection further exhibits, in a preferred manner, a latchable locking device, which prevents the fastening device from becoming inadvertently detached from the holding element.
In a preferred embodiment, the fastening device exhibits a plate which is disposed at a right-angle to the insertion member. This, for example, right-angled plate can exhibit four recesses which are disposed along the connecting lines joining the respectively opposing corners. Through these recesses can be guided clamping members, for example screw clamps or screwable hooks, which bring about a connection between the fastening device and the cross of the frame (stretcher). To increase stability, the fastening device can further exhibit extensions, which can be designed to be extensible and which form further supporting points on the frame (stretcher) or on the cross of the frame (stretcher).
The separable connection between the fastening device and the holding element has the advantage that the often very large canvas frames (stretchers) can be fastened without difficulty to the easel. Furthermore, the canvas frame (stretcher) can be easily exchanged with the aid of the separable connection between the holding element and the fastening device.
The easels according to the invention exhibit drive devices which enable the holding element to move in the vertical direction, parallel to the axis of the support element. As drive mechanisms, various solutions are conceivable here. As a preferred solution according to the invention, the easel exhibits a toothed rack which is disposed parallel to the support columns. This toothed rack exhibits notches in which a gearwheel, which is fastened to the holding element, engages. This gearwheel is driven, either directly or by means of a gear system, by an electric motor, which can run forwards or backwards. By the rotation of the gearwheel, the holding element then moves upwards or downwards, depending upon the direction of running of the electric motor.
In another embodiment, the easel exhibits a threaded spindle which is disposed parallel to the support columns. This spindle is guided through a sleeve having a counter-thread matching the thread of the spindle. This sleeve is firmly connected to the holding element. A rotation of the spindle now gives rise, depending upon the direction of rotation, to an upward or downward movement of the holding element. This spindle can be driven either directly by an electric motor or by means of a gear system of an electric motor.
In a further embodiment, the drive can be effected by a cable which is guided through appropriately disposed rollers such that, when the cable is wound onto a roller or unwound, the holding device can be moved upwards or downwards.
In a very particularly preferred embodiment, the holding element is moved up and down by means of a toothed belt, the toothed belt being guided over two toothed rollers, one of which, preferably the lower, is able to be driven by means of an electric motor.
The drive devices are driven, in a preferred manner, by electric motors, but other types of drive are also possible. Another type of drive would be, for example, a manual operation which is effected by the rotation of one or more cranks.
A transmission of the rotational movement from the electric motor to the element to be moved, especially to the spigot shaft for the plug-on part of the fastening device, is preferably effected by mutually engaging gearwheels.